After the North Elbingian Saxony was finally incorporated into the Franconian Empire in 810  , the Hammaburg was built – probably on behalf of Charlemagne – to secure the area occupied by the Franks (construction started around 817; excavations from July 2005). The church in it was probably elevated to the seat of a bishopric under Ansgar in 831 (from here missionary work in the north and east). The raid of the Danish Vikings under King Horich 845 and the destruction of the bishopric in 848 forced the union with the diocese of Bremen and the relocation of the bishopric there. According to relationshipsplus, Hamburg’s economic development began under the Schaumburgers, who were enfeoffed with the Counties of Holstein and Stormarn from 1110/11, and long-distance traders settled. In 1188 Count Adolf III. von Holstein († 1225) by Wirad von Boizenburg on the western bank of the Alster to add a port city with Luebian law (Neustadt with former main church Sankt Nicolai), whose important trade, customs and shipping privileges on the Lower Elbe on May 7, 1189 from Emperor Friedrich I. Barbarossa confirmed (details disputed). Hamburg’s development into a trading city was based on these privileges. The day of the exhibition is still celebrated today as “Overseas Day”.

As a result of the Hohenstaufen-Welf disputes, Hamburg came under Danish rule in 1201-27. The old town and the new town merged in 1216 to form a community with around 1,500 residents at that time. With the progressive damming of the Alster at Reesendamm (Jungfernstieg), the area in front of the new port city was increasingly opened up for settlement, and in the middle of the 13th century new quarters around Sankt Katharinen and (in the east) around Sankt Jacobi for merchants and craftsmen emerged on the diked islands south of the old town and carters. The fastening ring had to be expanded around 1260. The joint town hall was built around 1290 at the interface between the old town and the new town. Around 1300 Hamburg had around 5,000 residents.

Extensive self-government was established (1410 first recess between the council and the citizenship) and – supported by a lively export-oriented brewery that earned Hamburg the reputation of the “Hanseatic brewery” – the development of an important position in the Hanseatic west-east trade. The city stood out in the 14th century in the fight against the pirates on the North Sea, with the capture and execution of K. Störtebeker (1400) was decided victoriously. The beginnings of Hamburg’s territorial formation on the Lower Elbe (1375 acquisition of the Moorburg, 1394 of the Ritzebüttel fortress near Cuxhaven) made a significant contribution to securing shipping routes. At the end of the Middle Ages, Hamburg was one of the most important centers of the Hanseatic community, despite the first signs of recession, with around 12,000 to 14,000 residents. In 1510 the Hanseatic city, already designated as imperial direct under Emperor Siegmund (1410 / 33–37), was confirmed as a free imperial city; In 1648 it was confirmed by the Imperial Court of Justice, which was only recognized by Denmark in 1768 (Gottorper settlement).

The Reformation, which took place in Hamburg thanks to the moderating influence of J. Bugenhagen (first Protestant church ordinance 1529) carried out without severe internal shocks, favored a new economic upswing: among other things. Foundation of the first German and Northern European stock exchange by the “common merchant”, an association of merchants (1588), transfer of the pile of cloths of the English merchants’ guild “Merchant Adventurers” from Antwerp to Hamburg (1567). The immigration of religious refugees from the Spanish Netherlands in the second half of the 16th century, who brought with them new trades geared towards the processing of raw materials from overseas (e.g. sugar boiling), contributed to the development of Hamburg into an international staging area for Northern Europe into the 19th century. Century at. Around 1600 Hamburg had almost 40,000 residents, of which those new residents made up about a quarter.

The Dutch artillery captain J. van Valckenburgh built Hamburg into a mighty fortress in 1616-25, including the newly populated area around the St. Michaelis Church, built in 1606. The structural changes still determine the cityscape today (the inner Alster was cut off from the outer Alster in the course of the Lombard bridge built in 1688, former botanical garden, Holstenwall). Protected by this fortification, the city was spared the Thirty Years’ War (1618–48) and was able to defend itself in the subsequent period from the rivalry between the Danish rival establishment of Altona (city since 1664) and the Danish siege in 1686. In addition, the Brandenburg waterways (Müllrosekanal 1669) opened up a new, wide hinterland.

In 1665 Hamburg set up the first German Chamber of Commerce. The Hamburger Feuerkasse, founded in 1676, was the first fire insurance company in the world. Due to the economic boom, Hamburg also flourished in culture (including the founding of the first German opera in Hamburg in 1678; 1721–66 G. P. Telemann, 1766–88 C. P. E. Bach city ​​music directors; the poets B. H. Brockes and F. von Hagedorn). The internal strife between patrician and democratic groups at the end of the 17th century could be balanced out through imperial mediation from 1708-12. At that time, the Hamburg constitution, which was valid until 1860, was drawn up. After disputes with the Danish crown had ended in 1768, a period of peaceful development began, in which the population exceeded the 100,000 mark. G. E. Lessing was the first dramaturge of the newly opened National Theater from 1767–70; F. G. Klopstock lived in Hamburg from 1770–1803.

After the occupation by French troops (1806-14) and the continental blockade, the economic damage could be overcome relatively soon. It was possible to maintain and strengthen the position of the city as “Germany’s gateway to the world”.